/*
    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU General Public
    License as published by the Free Software Foundation; either
    version 2 of the license, or (at your option) any later version.
*/

package org.gjt.jclasslib.structures.attributes;

import org.gjt.jclasslib.structures.AttributeInfo;
import org.gjt.jclasslib.structures.InvalidByteCodeException;

import java.io.DataInput;
import java.io.DataOutput;
import java.io.IOException;

/**
 * Describes an <tt>InnerClasses</tt> attribute structure.
 *
 * @author <a href="mailto:jclasslib@ej-technologies.com">Ingo Kegel</a>
 * @version $Revision: 1.1 $ $Date: 2005/11/01 13:18:24 $
 */
public class InnerClassesAttribute extends AttributeInfo {

    /**
     * Name of the attribute as in the corresponding constant pool entry.
     */
    public static final String ATTRIBUTE_NAME = "InnerClasses";

    private static final int INITIAL_LENGTH = 2;

    private InnerClassesEntry[] classes;

    /**
     * Get the list of inner classes of the parent <tt>ClassFile</tt> structure
     * as an array of <tt>InnerClassesEntry</tt> structures.
     *
     * @return the array
     */
    public InnerClassesEntry[] getClasses() {
        return classes;
    }

    /**
     * Set the list of inner classes of the parent <tt>ClassFile</tt> structure
     * as an array of <tt>InnerClassesEntry</tt> structures.
     *
     * @param classes the array
     */
    public void setClasses(InnerClassesEntry[] classes) {
        this.classes = classes;
    }

    public void read(DataInput in)
            throws InvalidByteCodeException, IOException {

        int numberOfClasses = in.readUnsignedShort();
        classes = new InnerClassesEntry[numberOfClasses];

        for (int i = 0; i < numberOfClasses; i++) {
            classes[i] = InnerClassesEntry.create(in, classFile);
        }

        if (debug) debug("read ");
    }

    public void write(DataOutput out)
            throws InvalidByteCodeException, IOException {

        super.write(out);

        int numberOfClasses = getLength(classes);

        out.writeShort(numberOfClasses);
        for (int i = 0; i < numberOfClasses; i++) {
            classes[i].write(out);
        }
        if (debug) debug("wrote ");
    }

    public int getAttributeLength() {
        return INITIAL_LENGTH + getLength(classes) * InnerClassesEntry.LENGTH;
    }

    protected void debug(String message) {
        super.debug(message + "InnerClasses attribute with " + getLength(classes) + " classes");
    }

}
